Self-cleaning nozzle



` C. E. JACKSON SELF-CLEAN ING NOZ ZLE Oct. 2s, 1969 Filed Jan. 2, 1968www 07 TOENEKY.

United States Patent O California Y Filed Jan. 2, 1968, Ser. No. 695,087Int. Cl. BOSb 15/02 U.S. Cl. 239-118 11 Claims ABSTRACT F THE DISCLOSUREThe invention provides a self-cleaning spray nozzle assembly comprisingthe combination of a body having an inlet end and containing a nozzletube axially movable in response to iluid pressure changs. Fluid isrequired to enter the nozzle through one or more longitudinal slotstherein, the individual slot width'being less than the minimum fluidpassing internal dimension of the tube so that the slot effect is toscreen any otherwise nozzle clogging particles.

The nozzle is rendered self-cleaning bythe provision of means carried bythe body and enteringthe slot or slots so that the tube displacementresults in removal of temporarily retained slot clogging particles.

BACKGROUND OF THE INVENTION This invention relates to improvements inself-cleaning spray nozzles useable in any of various pressure spraysystems in which nozzle clogging by foreign particles may presentproblems. Illustrative of such nozzles are those used for lawnsprinkling, dishwashers and industrial spray washers.

Generally contemplated is the combination of a body adapted to receivefluid under pressure, and a nozzle tube within the body and axiallyreciprocable in response to fiuid pressure variations. Fluid delivery tothe nozzle is effected by longitudinally slotting the wall of the tube,the slot dimension being such as to block or screen from entry to thetube potential clogging foreign matter carried by the fluid.

The capacity of the nozzle tube for axial movement is utilized to freethe slot or slots from lodged particles, by providing suitable slotentering means carried by the body and serving to displace suchparticles as they are engaged during the tube movement.

An effective arrangement permissive of adequate flow through the nozzleis the use of diametrically opposed slots extended at least throughoutthe range of the nozzle reciprocation, and stationary clearing meansextending transversely of the tube through the slots.

The various features of the invention as well as the details ofillustrative embodiments will be more fully understood from thefollowing description of the accompanying drawing, in which:

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a view showing one form ofthe invention in axial cross section with the spray nozzle projected;

FIG. 2 is a similar view in which the nozzle tube is retracted;

FIG. 3 is a cross section on line 3-3 of FIG. 2;

FIGS. 4 and 5 are views similar respectively to FIGS. 1 and 2, showing avariational form of the invention; and

FIG. 6 is a cross section on line 6-6 of FIG. 5.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In reference first to FIGS. 1to 3, the nozzle assembly is shown to comprise a hollow body 10 threadedat 11 for reception within a pipe 12 which in the broad aspects3,474,968 Patented Oct. 28, 1969 ICC of the invention is to be regardedas any form of conduit for a liquid to be sprayed.

The body 10 contains an axially reciprocable spray nozzle in the form ofa tube 13 projecting through the body opening 14 and having integralpiston 15 received within the body bore 16, the piston being responsiveto fluid pressure in the chamber 17 to project the nozzle as in FIG. 1against the resistance of spring 18 contained within bore 19.

Inwardly the closed end 20 of the nozzle tube is projectable into theconduit 12 and beyond the closed end the tube has longitudinal parallelslots 21, typically four in number, through which fluid passes fromwithin the conduit and chamber 17 into the nozzle for projection in aspray pattern from its discharge end 22. As will be understood, thenozzle tube or its tip may be given any of various shape characteristicsto achieve desired spray patterns. The tube 13 is intersected by crossedmembers 23 in the nature of a spider which pass through the slots 21with sufficient clearance therein to allow pressure responsivereciprocation of the nozzle, the members 23 stationarily terminating at24 Within the body inlet end and being suitably retained therein as bylock ring 24a.

In response to liuid pressure from the conduit and within chamber 17 thepiston-equipped tube is projected against the resistance of spring 18 tothe limiting position of FIG. 1 for operation of the device under normalspray conditions. Upon interruption or reduction of the fluid pressure,spring 18 retracts the tube as to the position of FIG. 2 limited byengagement of the cross pieces 23 with the ends of slots 21. The latterare sufficient in number, length and width to pass the proper flowrequired for spraying from the tube. However, the slots otherwise aresized to be suiciently narrow to interrupt and in effect screen fromentry to the tube foreign materials that might tend to clog or soaccumulate in the tube as to interfere with the desired spray. Suchmaterials may tend temporarily to become lodged in the slots 21 but aredisplaced therefrom upon reciprocations of the tube by clean-outengagement with the Spider pieces 23, thus assuring continued properspray projection.

The form of the invention shown in FIGS. 4 to 6 (wherein partscorresponding to those in FIGS. 1 to 3 are given corresponding referencenumerals) precludes any leakage about the nozzle tube from a bodyopening and differs in that here the body 2S has the form of resilientbellows 26 which is self collapsible when relieved of internal fluidpressure, as in the condition of FIG. 5. The nozzle tube 13a passesthrough and is fixed and sealed at 27 to the head 28 of the bellows sothat in response to operative spray liuid pressure the bellows expandsto the FIG. 4 condition limited by the engagement of the spider 23 withthe ends of slots 21. As before, relief and increase of fluid pressuresreciprocates the nozzle tube, enabling the spider to clear out the slotsfrom any materials lodged therein.

I claim:

1. A self-cleaning nozzle assembly comprising:

(a) a hollow body having an inlet end adapted to receive fluid from aconduit,

(b) an axially reciprocable nozzle tube contained within the body,

(c) means whereby the nozzle tube is responsive to increasing anddecreasing inlet fluid pressures respectively to move between projectedand retracted positions,

(d) said tube being longitudinally slotted to pass fluid from within thebody into the tube, and

(e) means carried by the body and extending into the tube slot to effectremoval of clogging material upon axial displacement of the tube.

2. A nozzle assembly according to claim 1, in which said means (c)comprises a piston carried by the tube causing the tube to project outthrough an opening in the body in response to increasing duid pressure,and means reversely biasing the tube.

3. A nozzle assembly according to claim 1, in which said means (c)comprises a bellows portion of said body to which the tube is attachedand which is expansible and contractable to project and retract thetube.

4. A nozzle assembly according to claim 1, in which said inlet end ofthe body is threaded for connection with a conduit.

5. A nozzle assembly according to claim 1, in which said means (e) ispositioned Within the inlet end of the body.

6. A nozzle assembly according to claim 1, in which said tube isreciprocable out of the inlet end of the body.

7. A nozzle assembly according to claim 1, in which said tube has aplurality of circularly spaced slots (d) and said means (e) is receivedwithin said slots.

8. A nozzle assembly according to claim 7, in which said means (e)comprises cross members intersecting within the tube and stationarilypositioned Within the body.

9. A nozzle assembly according to claim 1, in which the slot width inthe tube is less than the minimum internal fluid passing diameter of thetube.

10. A nozzle assembly according to claim 1, in which the tube has aplurality of circularly spaced parallel slots (d) the width of each'being less than the minimum internal uid passing diameter of the tube,and said means (e) is received within said slots.

11. A nozzle assembly according to claim 9, in which said means (c)comprises a piston carried by the tube causing the tube to project inresponse to increasing uid pressure, and means reversely biasing thetube.

References Cited UNITED STATES PATENTS 1,094,124 4/1914 coen 239-1172,097,696 11/1937 Macdonan 239-118 2,123,826 7/1938` Dinrrrarr 239-1182,179,184 11/1939 Hodge 239-118 3,017,120 1/1962 Friam et a1. 239-117EVERETT W. KIRBY, Primary Examiner Us. c1. XR. 239-123

